RV.Net Open Roads Forum: Tow Vehicles: DEF when towing

RV Blog

  |  

RV Sales

  |  

Campgrounds

  |  

RV Parks

  |  

RV Club

  |  

RV Buyers Guide

  |  

Roadside Assistance

  |  

Extended Service Plan

  |  

RV Travel Assistance

  |  

RV Credit Card

  |  

RV Loans

Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Posting Help and Support  |  Contact  

Search:   Advanced Search

Search only in Tow Vehicles

Open Roads Forum  >  Tow Vehicles

 > DEF when towing

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 3  
Prev  |  Next
Sponsored By:
JKJavelin

Milwaukee, WI

Senior Member

Joined: 12/31/2016

View Profile



Good Sam RV Club Member

Offline
Posted: 03/05/22 08:55pm Link  |  Quote  |  Print  |  Notify Moderator

My fifth wheel is just under 12,000 lbs. My Ram's DEF mileage when towing is about 450 mpg.
JK


2018 Ram 3500 Laramie Cummins 6.7
2016 Open Range RF316RLS
Titan Disc Brakes
Trailair pinbox
Morryde SRE-4000 w/ wetbolt kit
Demco Autoslide
570 watts of Solar

2017- 21 Nights
2018- 75 Nights
2019- 138 Nights
2020- 72 Nights
2021- 122 Nights
2022- 85 Nights

ktmrfs

Portland, Oregon

Senior Member

Joined: 06/22/2005

View Profile


Offline
Posted: 03/05/22 09:30pm Link  |  Quote  |  Print  |  Notify Moderator

Michelle.S wrote:

I average 450 to 500 miles per gallon of DEF pulling 19.5K.
I've never gotten the 1000 mile warning, generally get the warning that I have 250 to 400 miles before DEF Empty.


GM gives a warning at 30% DEF level. that's about 1.5 Gallons of DEF= 100-150 gallon of diesel. That's at least 1000 miles range when towing.

When we are traveling long distances, I just carry a 2.5 gallon jug of DEF. If I get a "30%" warning, next overnight stop I stuff in 2.5 gallons and good to go.


2011 Keystone Outback 295RE
2004 14' bikehauler with full living quarters
2015.5 Denali 4x4 CC/SB Duramax/Allison
2004.5 Silverado 4x4 CC/SB Duramax/Allison passed on to our Son!


ksss

Eastern Idaho

Senior Member

Joined: 02/19/2011

View Profile


Offline
Posted: 03/05/22 09:58pm Link  |  Quote  |  Print  |  Notify Moderator

The '20 and newer Duramax trucks have a complete gauge. I have an '18 that does the 30% notification. I am not sure why they didn't put a full gauge in the older trucks, but it really isn't the deal people make it out to be. When it kicks off at 30% you still have plenty of time to get DEF, even when pulling heavy. I don't get excited about the DEF in my '20 until it gets below half anyway so it really doesn't change anything for me.


2020 Chevy 3500 CC 4X4 DRW D/A
2013 Fuzion 342
2011 RZR Desert Tan
2012 Sea Doo GTX 155
2018 Chevy 3500HD CC LB SRW 4X4 D/A
2015 Chevy Camaro ZL1

Toolguy5

Columbia Station, Ohio

Senior Member

Joined: 09/08/2003

View Profile





Offline
Posted: 03/06/22 09:27am Link  |  Quote  |  Print  |  Notify Moderator

I have a 2020 it has a gauge and the fill port is in the fuel door next to diesel port.
I had a 2015 before it it gave the 30%. The 2020 is better with the gauge and fill port. There was a recall on it shortly after they came out. Gauge was not working properly.

As i stated before i Have an appointment Tuesday for the dealer to look at. I may have sludge from when it got cold and I received warning poor DEF. That was after dealer filled it up.


Dan & Patty
Miss Pickles the Pomeranian Princess
2020 GMC 3500 Sierra Denali 6.6 Duramax / Allison tranny
2021 Jayco Eagle 319MLOK
BWRVK 3710 companion
Maddy the Pampered Pom @ Rainbow Bridge 12-3-2013

Cummins12V98

on the road

Senior Member

Joined: 06/03/2012

View Profile


Offline
Posted: 03/06/22 11:01am Link  |  Quote  |  Print  |  Notify Moderator

I recently filled mine to the top then towed my 35k combined load from NW WA to So cal. I filled to the top at a Truck Stop and calculated at 347mpg. My fuel consumption was around 123 gallons 9mpg.

I also can easily add a 2.5 gallon DEF at 1/2 tank.


2015 RAM LongHorn 3500 Dually CrewCab 4X4 CUMMINS/AISIN RearAir 385HP/865TQ 4:10's
37,800# GCVWR "Towing Beast"

"HeavyWeight" B&W RVK3600

2016 MobileSuites 39TKSB3 highly "Elited" In the stable

2007.5 Mobile Suites 36 SB3 29,000# Combined SOLD

Lantley

Ellicott City, Maryland

Senior Member

Joined: 08/23/2005

View Profile


Offline
Posted: 03/06/22 11:35am Link  |  Quote  |  Print  |  Notify Moderator

ksss wrote:

I am not sure why they didn't put a full gauge in the older trucks, but it really isn't the deal people make it out to be. When it kicks off at 30% you still have plenty of time to get DEF,

Well that's the catch. I now carry a jug of DEF in the RV during camping season. My first experience with the DEF warning came when the display said 500 miles until limp mode.
I thought fine I'm 200 miles from home I'm good.
About 20 miles later display said 150 miles until limp mode.
At that point I could not consider the milage accurate. Nor could I trust it. So I left the interstate to find DEF.
I found it at a little gas station in congested suburbia in northern VA. THe whole expeince was a huge pain in the A@$%*.
So now I keep a jug of DEF on hand.Maybe a good idea anyway,but I don't carry a jug of diesel for just in case! However if you don't have a gauge, just in case can happen very easily.
My dually is also my daily driver. I'm not towing 100% of the time.
MY DEF usage is not consistant. Whatever strategy or algorithym is being used to trigger the warning light is not accurate or foolproof.
With that in mind the truck needs a gauge plain and simple. All the work arounds are ridicoulous.
Even more ridicoulous is that it took them until 2020 to figure out they need a DEF gauge...that's quite a few model years with no gauge.


19'Duramax w/hips,12'Open Range,Titan Disc Brake
BD3,RV safepower,22" Blackstone
Ox Bedsaver,RV760 w/BC20,Glow Steps, Enduraplas25,Pedego
BakFlip,RVLock,5500 Onan LP,Prog.50A surge,Hughes autoformer
Porta Bote 8.0 Nissan,Sailun S637
Correct Trax,Splendide


ksss

Eastern Idaho

Senior Member

Joined: 02/19/2011

View Profile


Offline
Posted: 03/06/22 01:11pm Link  |  Quote  |  Print  |  Notify Moderator

I agree that the effort it took to put in the system that they did, they could have given it a full gauge. Does that require "some work arounds" well maybe. I am not sure if the issue is not a full gauge or the algorithym not being correct regardless of whether you can see the amount that it indicates. I too have seen the issues you mention about the rate of burn not being consistent. I just periodically top it off. I guess that is my work around. I have other equipment that burns DEF so I just empty my partial containers in my pickups and I always have it with me. So for me it is just a habit I have developed. Periodically topping it at every other fill up would probably be similar. DEF itself is also ridiculous, but they don't run without it so...

Lantley

Ellicott City, Maryland

Senior Member

Joined: 08/23/2005

View Profile


Offline
Posted: 03/06/22 01:23pm Link  |  Quote  |  Print  |  Notify Moderator

I think we are on the same page. My lack of a DEF gauge is not the crisis of the century. There are work arounds "Like be sure you have DEF jug with you in case you run out"...LOL.
If lack of DEF gauge is the biggest negative of my truck than I'm doing OK!

Cummins12V98

on the road

Senior Member

Joined: 06/03/2012

View Profile


Offline
Posted: 03/06/22 02:35pm Link  |  Quote  |  Print  |  Notify Moderator

Lantley said: "If lack of DEF gauge is the biggest negative of my truck than I'm doing OK!"


I agree! Really can't be that big of a deal to simply add to it based on the type of driving you have been doing. Always have some fresh water to rinse away any spilled DEF. If using a funnel or reusing the fill tube provided be sure to rinse thoroughly.

Toolguy5

Columbia Station, Ohio

Senior Member

Joined: 09/08/2003

View Profile





Offline
Posted: 03/06/22 03:01pm Link  |  Quote  |  Print  |  Notify Moderator

I also carry jugs of DEF when towing so I have it.

But when your gauge is showing almost a full tank and you get a warning low DEF something else is going on.

Hardly use any DEF when not towing. Usually top it off at oil changes.

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 3  
Prev  |  Next

Open Roads Forum  >  Tow Vehicles

 > DEF when towing
Search:   Advanced Search

Search only in Tow Vehicles


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:




© 2022 CWI, Inc. © 2022 Good Sam Enterprises, LLC. All Rights Reserved.